I am currently trying to figure out the best way to file / sand / mill code Flat Bottom 82 switch rails and Google is not bringing up very good information! I may be getting too hung up on the accuracy and maths perhaps?
I have gathered up the various planning lengths required for each of the 4 switch sizes that I am using and calculated their angles based on a foot size of 1.86 being reduced to 0.93 (50%) as follows:

I have plenty of files to hand
I have a benchtop disc sander (180 grit disc at the moment)
As I am a British Expat based in Calgary, Canada, I have tried a jig from hand laid tracks but it is simply too short.

Now I have taken some rail in an attempt to make a CV blade, marked out 48.74 with a sharpie. What do I do now? Those angles are so small to do accurately by eye.

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